The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of making a decision about when it's a good idea to plant sweet williams is to consult the USDA zone info for Bothell.

Planting Calendar for Sweet Williams

Frost tolerance for sweet williams:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since sweet williams are moderately cold tolerant you can plant them a little bit earlier in the year than other frost tender plants.

The earliest that you can plant sweet williams in Bothell is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant sweet williams and expect a good harvest is probably September. Any later than that and your sweet williams may not have a chance to grow to maturity. If you are starting your sweet williams indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Bothell the average date of last frost happens on March 15. In the coldest months of winter you can expect an average low temperature of 15°F.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Bothell and it changes from year to year. Half of the time in Bothell there is a last frost after March 15 so be sure to be ready to protect your sweet williams if you have a surprise late frost.

USDA Zone Info for Bothell

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Bothell

You may be interested in your other planting guides for Bothell.